The present invention relates to the field of wireless communication and in particular to an adaptive receiver.
The field of wireless communications is rapidly expanding. In particular, cellular communication systems are experiencing phenomenal growth. Likewise, cordless telephones are in widespread use.
Each mobile station, whether a cordless or cellular telephone, operates using power supplied by an associated battery. Each mobile station continually draws power from the battery while in standby mode or during an active communication link. The mobile unit draws the most power during periods of an active communication link. In particular, the receiver, which is responsible for obtaining, filtering, decoding and synthesizing the incoming signal, comprises a large percentage of total mobile unit power usage during an active communication link. This is especially true when the communication system comprises a modem cellular system, such as Global System for Mobile Communication (GSM) or a system adopting Code Division Multiple Access (CDMA) techniques. Modem communication systems adopt these complex coding schemes to increase both system capacity and voice quality.
The present invention is directed to unique methods and apparatus for controlling power utilization in a wireless communication receiver. A representative system, among others, comprises a signal properties evaluation module, an analog to digital converter, and an analog to digital converter control module. The signal properties evaluation module evaluates the stability of a received signal, and provides an indication of the stability. The analog to digital converter control module responds to the signal properties evaluation module to select the precision of the analog to digital converter based upon the indication of the stability. The analog to digital converter has at least two modes of operation, and is responsive to the signal properties evaluation module to operate in at least one of two modes based upon based upon the stability. The first mode comprises operation at a first precision and said second mode comprises operation at a second precision. The analog to digital converter responds to the signal properties evaluation module so as to limit the amount of power consumed by the wireless communications device.
A representative method, amoung others, comprises the steps of: receiving a signal; monitoring the characteristics of the incoming signal; evaluating the stability of the incoming signal; and altering the precision of an analog to digital converter based on the evaluated stability of the incoming signal so as to limit the amount of power consumed by said wireless communications receiver.